// 委托理论 
Task = { 
    setID: function(ID) { this.id = ID; }, 
    outputID: function() { console.log( this.id ); } 
   }; 
   // 让 XYZ 委托 Task 
   XYZ = Object.create( Task ); 
   XYZ.prepareTask = function(ID,Label) { 
    this.setID( ID ); 
    this.label = Label; 
   }; 
   XYZ.outputTaskDetails = function() { 
    console.log(this,1234);
    this.outputID(); 
    console.log( this.label ); 
   }; 
   // ABC = Object.create( Task );
   XYZ.prepareTask('123',555)
 XYZ.outputTaskDetails();
   